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Viruses Oct 2016Viruses must continuously evolve to hijack the host cell machinery in order to successfully replicate and orchestrate key interactions that support their persistence.... (Review)
Review
Viruses must continuously evolve to hijack the host cell machinery in order to successfully replicate and orchestrate key interactions that support their persistence. The type-1 human immunodeficiency virus (HIV-1) is a prime example of viral persistence within the host, having plagued the human population for decades. In recent years, advances in cellular imaging and molecular biology have aided the elucidation of key steps mediating the HIV-1 lifecycle and viral pathogenesis. Super-resolution imaging techniques such as stimulated emission depletion (STED) and photoactivation and localization microscopy (PALM) have been instrumental in studying viral assembly and release through both cell-cell transmission and cell-free viral transmission. Moreover, powerful methods such as Forster resonance energy transfer (FRET) and bimolecular fluorescence complementation (BiFC) have shed light on the protein-protein interactions HIV-1 engages within the host to hijack the cellular machinery. Specific advancements in live cell imaging in combination with the use of multicolor viral particles have become indispensable to unravelling the dynamic nature of these virus-host interactions. In the current review, we outline novel imaging methods that have been used to study the HIV-1 lifecycle and highlight advancements in the cell culture models developed to enhance our understanding of the HIV-1 lifecycle.
Topics: Cells, Cultured; HIV-1; Host-Pathogen Interactions; Humans; Optical Imaging; Staining and Labeling; Virology
PubMed: 27775563
DOI: 10.3390/v8100288 -
Journal of Viral Hepatitis Apr 2015Viral hepatitis claims one million lives each year. Scaling up treatment for hepatitis B and C in resource-limited settings is not possible without access to reliable... (Review)
Review
Viral hepatitis claims one million lives each year. Scaling up treatment for hepatitis B and C in resource-limited settings is not possible without access to reliable diagnostic tools. This article gives an overview of current technologies and the pipeline for easy-to-use assays for serological and virological analyses, which can be performed at the site of patient care ('point-of-care assays'). Furthermore, the utility of dried blood spots for hepatitis B and C viral load testing is discussed. In addition to simple and reliable diagnostics, there is a need for a sustainable funding scheme and generic production of antiviral drugs to reduce the burden of viral hepatitis worldwide.
Topics: Diagnostic Tests, Routine; Hepatitis B; Humans; Point-of-Care Systems; Serology; Viral Load; Virology
PubMed: 25762459
DOI: 10.1111/jvh.12385 -
Infection, Genetics and Evolution :... Mar 2015Next-generation sequencing (NGS) technology offers new opportunities for understanding the evolution and dynamics of viral populations within individual hosts over the... (Review)
Review
Next-generation sequencing (NGS) technology offers new opportunities for understanding the evolution and dynamics of viral populations within individual hosts over the course of infection. We review simple methods for estimating synonymous and nonsynonymous nucleotide diversity in viral genes from NGS data without the need for inferring linkage. We discuss the potential usefulness of these data for addressing questions of both practical and theoretical interest, including fundamental questions regarding the effective population sizes of within-host viral populations and the modes of natural selection acting on them.
Topics: Animals; Genes, Viral; Genetic Variation; Genetics, Population; Genome, Viral; Haplorhini; High-Throughput Nucleotide Sequencing; Humans; Sequence Analysis, DNA; Sequence Analysis, RNA; Virology
PubMed: 25481279
DOI: 10.1016/j.meegid.2014.11.026 -
Burns : Journal of the International... Aug 2017Burn-related immunosuppression can promote human herpesviridae infections. However, the effect of these infections on morbidity and mortality after pediatric burn...
OBJECTIVE
Burn-related immunosuppression can promote human herpesviridae infections. However, the effect of these infections on morbidity and mortality after pediatric burn injuries is unclear.
METHODS
We retrospectively analyzed pediatric patients with burns ≥10% of the total body surface area (TBSA) who were admitted between 2010 and 2015. On clinical suspicion of a viral infection, antiviral therapy was initiated. Viral infection was confirmed via Tzanck smear, viral culture, and/or PCR. Study endpoints were mortality, days of antiviral agent administration, type of viral test used, type of viral infection, and length of hospitalization.
RESULTS
Of the 613 patients were analyzed, 28 presented with clinically diagnosed viral infections. The use of Tzanck smears decreased over the past 5 years, whereas PCR and viral cultures have become standard. Patients with viral infections had significantly larger burns (53±15% vs. 38±18%, p<0.001); however, length of stay per TBSA burn was comparable (0.5±0.4 vs. 0.6±0.2, p=0.211). The most commonly detected herpesviridae was herpes simplex virus 1. Two patients died due to sepsis, which was accompanied by HSV infection. The mortality rate among all patients (2.7%) was comparable to that in the infected group (7.1%, p=0.898). Acyclovir was given systemically for 9±8days (N=76) and/or topically for 9±9days for HSV (N=39, combination of both N=33). Ganciclovir was prescribed in three cases for CMV.
CONCLUSIONS
Viral infections occur more commonly in patients suffering from larger burns, and HSV infections can contribute to mortality.
Topics: Adolescent; Antiviral Agents; Burns; Child; Child, Preschool; Female; Herpesviridae; Herpesviridae Infections; Humans; Infant; Male; Polymerase Chain Reaction; Retrospective Studies; Risk Factors; Sepsis; Virology; Wound Infection
PubMed: 28420570
DOI: 10.1016/j.burns.2017.01.032 -
Viruses Aug 2016In the last 25 years, the scientific and public attention paid to bunyaviruses has increased considerably.[...].
In the last 25 years, the scientific and public attention paid to bunyaviruses has increased considerably.[...].
Topics: Bunyaviridae; History, 20th Century; History, 21st Century; Host-Pathogen Interactions; Humans; Viral Matrix Proteins; Virology; Virus Replication; Viruses
PubMed: 27517952
DOI: 10.3390/v8080224 -
Virologica Sinica Oct 2016Three-dimensional (3D) culture models are physiologically relevant, as they provide reproducible results, experimental flexibility and can be adapted for high-throughput... (Review)
Review
Three-dimensional (3D) culture models are physiologically relevant, as they provide reproducible results, experimental flexibility and can be adapted for high-throughput experiments. Moreover, these models bridge the gap between traditional two-dimensional (2D) monolayer cultures and animal models. 3D culture systems have significantly advanced basic cell science and tissue engineering, especially in the fields of cell biology and physiology, stem cell research, regenerative medicine, cancer research, drug discovery, and gene and protein expression studies. In addition, 3D models can provide unique insight into bacteriology, virology, parasitology and host-pathogen interactions. This review summarizes and analyzes recent progress in human virological research with 3D cell culture models. We discuss viral growth, replication, proliferation, infection, virus-host interactions and antiviral drugs in 3D culture models.
Topics: Animals; Cell Culture Techniques; Humans; Models, Biological; Virology; Viruses
PubMed: 27822716
DOI: 10.1007/s12250-016-3889-z -
Methods (San Diego, Calif.) Aug 2017Fluorescent tags constitute an invaluable tool in facilitating a deeper understanding of the mechanistic processes governing virus-host interactions. However, when... (Review)
Review
Fluorescent tags constitute an invaluable tool in facilitating a deeper understanding of the mechanistic processes governing virus-host interactions. However, when selecting a fluorescent tag for in vivo imaging of cells, a number of parameters and aspects must be considered. These include whether the tag may affect and interfere with protein conformation or localization, cell toxicity, spectral overlap, photo-stability and background. Cumulatively, these constitute challenges to be overcome. Bluetongue virus (BTV), a member of the Orbivirus genus in the Reoviridae family, is a non-enveloped virus that is comprised of two architecturally complex capsids. The outer capsid, composed of two proteins, VP2 and VP5, together facilitate BTV attachment, entry and the delivery of the transcriptionally active core in the cell cytoplasm. Previously, the significance of the endocytic pathway for BTV entry was reported, although a detailed analysis of the role of each protein during virus trafficking remained elusive due to the unavailability of a tagged virus. Described here is the successful modification, and validation, of a segmented genome belonging to a complex and large capsid virus to introduce tags for fluorescence visualization. The data generated from this approach highlighted the sequential dissociation of VP2 and VP5, driven by decreasing pH during the transition from early to late endosomes, and their retention therein as the virus particles progress along the endocytic pathway. Furthermore, the described tagging technology and methodology may prove transferable and allow for the labeling of other non-enveloped complex viruses.
Topics: Animals; Bluetongue virus; Host-Pathogen Interactions; Microbiological Techniques; Virology; Virus Internalization
PubMed: 28802715
DOI: 10.1016/j.ymeth.2017.08.004 -
Viruses Nov 2015In the nearly two decades since the popularization of green fluorescent protein (GFP), fluorescent protein-based methodologies have revolutionized molecular and cell... (Review)
Review
In the nearly two decades since the popularization of green fluorescent protein (GFP), fluorescent protein-based methodologies have revolutionized molecular and cell biology, allowing us to literally see biological processes as never before. Naturally, this revolution has extended to virology in general, and to the study of alpha herpesviruses in particular. In this review, we provide a compendium of reported fluorescent protein fusions to herpes simplex virus 1 (HSV-1) and pseudorabies virus (PRV) structural proteins, discuss the underappreciated challenges of fluorescent protein-based approaches in the context of a replicating virus, and describe general strategies and best practices for creating new fluorescent fusions. We compare fluorescent protein methods to alternative approaches, and review two instructive examples of the caveats associated with fluorescent protein fusions, including describing several improved fluorescent capsid fusions in PRV. Finally, we present our future perspectives on the types of powerful experiments these tools now offer.
Topics: Alphaherpesvirinae; Biomedical Research; Host-Pathogen Interactions; Luminescent Proteins; Recombinant Fusion Proteins; Staining and Labeling; Virology
PubMed: 26610544
DOI: 10.3390/v7112915 -
Viruses Aug 2015The HPV viral lifecycle is tightly linked to the host cell differentiation, causing difficulty in growing virions in culture. A system that bypasses the need for... (Review)
Review
The HPV viral lifecycle is tightly linked to the host cell differentiation, causing difficulty in growing virions in culture. A system that bypasses the need for differentiating epithelium has allowed for generation of recombinant particles, such as virus-like particles (VLPs), pseudovirions (PsV), and quasivirions (QV). Much of the research looking at the HPV life cycle, infectivity, and structure has been generated utilizing recombinant particles. While recombinant particles have proven to be invaluable, allowing for a rapid progression of the HPV field, there are some significant differences between recombinant particles and native virions and very few comparative studies using native virions to confirm results are done. This review serves to address the conflicting data in the HPV field regarding native virions and recombinant particles.
Topics: Humans; Papillomaviridae; Papillomavirus Infections; Recombination, Genetic; Virion; Virology; Virus Cultivation
PubMed: 26247955
DOI: 10.3390/v7082823 -
International Journal of Molecular... Oct 2020Virus detection in natural and clinical samples is a complicated problem in research and diagnostics. There are different approaches for virus isolation and... (Review)
Review
Virus detection in natural and clinical samples is a complicated problem in research and diagnostics. There are different approaches for virus isolation and identification, including PCR, CRISPR/Cas technology, NGS, immunoassays, and cell-based assays. Following the development of genetic engineering methods, approaches that utilize cell cultures have become useful and informative. Molecular biology methods allow increases in the sensitivity and specificity of cell cultures for certain viruses and can be used to generate reporter cell lines. These cell lines express specific reporter proteins (e.g., GFP, luciferase, and CAT) in response to virus infection that can be detected in a laboratory setting. The development of genome editing and synthetic biology methods has given rise to new perspectives regarding the design of virus reporter systems in cell cultures. This review is aimed at describing both virology methods in general and examples of the development of cell-based methods that exist today.
Topics: Animals; Cell Culture Techniques; Genes, Reporter; Genetic Engineering; Humans; Synthetic Biology; Virology; Viruses
PubMed: 33121109
DOI: 10.3390/ijms21217978